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chemical composition; maize is modified as to its size; rye varies 
very little with change of conditions, except as to the effect upon the 
straw; but, as we have seen, wheat changes both its external appear- 
ance and its chemical constituents. 
With regard to maize, the high ripening temperature of the South- 
ern States appears to diminish the size of the kernel and prevent a 
large formation of starch. But the variations in size peculiar to the 
varieties are much smaller than variations that are due to the climate 
and soil, thus Dent varieties of corn from Tennessee and Indiana have 
been Fanta weighing, respectively, 64.1 and 13.9 grams per 100 ker- 
pels, or a ratio of 5 to 1 in the weights of the kernels. Hence a 
comparison of the yield per acre by the weights of the crops would 
differ very much from a comparison by volumes in bushels. The per- 
centage of albuminoids varies very much less in the large and small 
kernels of maize. 
As to oats, the climatic surroundings cause a very large variation 
in their physical appearance. The extreme weights per bushel are 
48.8 and 24.7 pounds; the extreme ratios in the weight of the kernel, 
with reference to the weight of the kernel plus the hull, are 79 and 55 
per cent. The average composition all over the country as to the 
percentage of albuminoids is between 12 and 10 per cent, except in a 
few extreme cases of 9 and 19 per cents, which are as lable to occur 
in one locality as in another. 
Barley is not as variable in composition and appearance as wheat 
and oats; the extreme weights per bushel are 60.2 and 50.4 pounds, 
and the extreme weights of 100 kernels are 4.900 and 2.630 grams; 
the extreme percentages of albuminoids are 14.88 and 8.75. For 
malting purposes the large quantity of albuminoid is not desirable, 
while starch is desirable. 
WHEAT—GENERAL RELATIONS TO CLIMATE AND SOIL. 
In his tenth census report Professor Brewer says: 
While the cultivation of wheat in a commercial sense is determined 
by a complicated set of conditions, in an agricultural sense the matter 
is very much simpler. The yield and quality of the crop practically 
depends upon but five conditions—the climate, the soil, the variety 
cultivated, the method of cultivation, and the lability to destruction 
by insects. Even under poor cultivation and exemption from insect 
depredations, if the other three conditions are favorable good crops 
of wheat of good quality may be very often grown, and in a good 
climate and with a good v ariety of wheat an excellent quality may be 
grown even where the soil is comparatively poor. The yield may 
be small, but the grain itself will be good. 
As regards soils, we may say ina ‘general way that light clays and 
heavy loams are the best for wheat. On the one hand, very heavy 
